1. Field of the Invention
The present invention relates generally to a method and apparatus for boosting the resolution and drawing rate of a computer graphics system which is designed to work with a visual display device, such as a high resolution cathode ray tube display. The method and apparatus obtains these advantages by eliminating the need for a high data output rate from the graphics system which would be otherwise required for a high resolution cathode ray tube through the use of a virtual cathode ray tube apparatus comprising a self-refreshing buffer system which can interface to and refresh the display device. The method and apparatus further permit the computer graphics system to provide all features it would normally provide because it simulates a conventional cathode ray tube in all its characteristics except refresh rate.
2. Description of the Prior Art
Many computer graphics systems presently interface directly to a cathode ray tube, but have an amount of memory bandwidth required to refresh the display as the limiting factors for their drawing performance and resolution support. In general, these prior known graphics systems are unable to use new generation multi-port video memories to alleviate this memory bandwidth bottleneck without losing valuable features. Often this is because the computer graphics system incorporates features which require data not located in sequential memory locations, and these video memories must be sequentially accessed. As a result, design of these systems forces a choice between the use of the full feature set on one hand and resolution and performance on the other.
Software compatibility between the two design classes is also limited.
In contrast, the present invention permits increasing both resolution and drawing performance while supporting the full range of features, including those requiring random access.